Looks like a fun set up. You have clearly put some thought and work into it.

Probably you would benefit from a jib to increase the sail area and thus speed. To do that you'd need to stay the mast (because the small Hobie mast would not be strong enough to support both main and jib and drive the heavier boat you have created) but that would be easy to do given the additional width created by the amas and kayak-aka (or is that "kayakaka" ?!).

Another thought is that I believe there are kayak akas other than the Hobie Island ones available off the shelf - being smaller and lighter these might work better than than the kayakaka (I am not thinking about inflatable ones but plastic ones that I am sure I have seen photos of somewhere on these forums) Please excuse me if I am telling you what you already know - I am no expert! - but from what I read trimaran design is not as simple as it looks i.e. it is not a case of just bolting three hulls together: the weight and design of the akas and the central hull are all considered together to create a boat which performs in a particular way. For example if the akas have too much buoyancy, in a strong wind the central hull can lift out of the water and the boat will tend to tip over the leeward aka. Boats can be designed specifically to do this (so that the boat can be sailed on one hull only - the aka hull - for speed), but they can also be designed in such a way so that the leeward aka sinks when the sails are overpowered thus spilling wind (for safety) as on a conventional monohull (I think the Island is designed more for safety - and the mast bends in any case so you would probably have to be out in a hurricane to get the central hull to lift). Nonethelees, while you may not be too concerned about these design details (looks like you are going to have some fun with the boat as is!) you may be of the mind to tinker about with different set-ups in which case, in addition to the idea of running up extra canvas, hulls design might be another outlet for your creativity.